Fight to Date
by Destielixer
Summary: Mortal Instruments AU. When the High Warlock Balthazar is ousted from his house due to a demon problem, he comes to stay at the Institute. Of course he does his research on the inhabitants or just one in particular, the Shadowhunter Castiel. They fight over this small little thing and if Balthazar wins, he wants a date with Castiel. ONESHOT. M in case. Fill for SRS2013BR1 prompt.


**AN: So here's another of my entry into SRS2013BR1. This is the fill to a prompt about having a Mortal Instruments AU by twinkie_pie on the community. So yep, here's the fill, do leave me a comment guys to let me know what you thought of it and thanks for reading!**

**Disclaimer: I do not own Supernatural or Mortal Instruments. This story is 100% fanmade for the fans by a fan. **

**Character List**

Castiel – Alec

Balthazar – Magnus

Bobby – Hodge

Ruby – Isabelle

Dean – Jace

* * *

Fight to Date

"Come on Castiel it's just a bit of harmless digging after all why are you so obsessed about it?" the High Warlock, Balthazar was saying as he folded his arms over his chest, his appearance calm. He wasn't going to admit to a thing.

"It involves me that's why. You don't have to dig on stuff about me you can just ask me..." Castiel muttered.

Balthazar shrugged nonchalantly, "I have no idea what you are talking about Castiel, no idea at all. Now why would I be digging for information about you hmm? I'm certainly not interested in you," he lied.

Castiel chose to ignore that remark, "Oh really no idea?" he asked as he holds out the papers with his name on it to Balthazar, "Do they look familiar?"

The warlock swallowed, his face still a passive mask as he replied, "No, I have never seen those papers before. Not until you showed me that is."

Castiel shook his head now rolling his eyes. His patience snapped and he throws the papers at the warlock, "Stop freaking lying will you Balthazar? It's good enough that you've come here to live at the Institute with us. And you're lucky that Dean even allows you to stay here. I for one would have kicked you out the moment I saw you Warlock. So tell me now, why were you searching for information on me?"

Balthazar expected this from him, Castiel was after all a Shadowhunter and like all the other Nephilim his attitude was no different, "Yes, yes the whole Downworlders being inferior issue once again. I should have expected this from you," he says trying to feel anger at the statement but what he felt was instead a deep sense of disappointment and a dull ache. "I guess I should be counting my blessings and not speaking back to the high and mighty Shadowhunter isn't that right?"

He turns about to leave the room before he whirls back around, prodding Castiel's chest with a finger now as he said, "And for your information, Castiel the Shadowhunter you should really think twice before you think so highly of yourself. I am the High Warlock of Brooklyn, not just any random warlock. I don't have to report to you before I get information on you. I don't answer to anyone but myself." He paused then added, "I didn't dig around information regarding you alright? You can ask Bobby about that if you don't believe me."

Castiel flicked his finger away quickly, trying to quell the shudder that had coursed through him at the Warlock's sudden touch, "Bobby" he scoffed, "He's a liar. I'm never going to trust a word he says, there's just something off about him," he pauses before continuing, "Fine. If you don't want to tell me I'll find it out on my own," he says as he pushes Balthazar out of his room now, kicking the papers out after him before shutting the door in a haste.

He leans against the thick wooden door now, heaving a sigh, "Fuck. He shouldn't even be here," he whispers closing his eyes. Castiel can still clearly remember the Warlock's comment about his pretty blue eyes. He gulps, biting his lower lip as he tried to squash the growing feelings inside him, "He's creepy. Just bear with it Cas. He'll be gone once his home gets fixed…which is I don't know how long. I so do not want to meet him at dinner…"

* * *

Ruby has just finished laying down the last of the cutlery for dinner, smoothing the side of the table cloth from a crease now as she looks at the perfect setting for dinner. Then she yells, "GUYS IT'S TIME FOR DINNER!" As usual the boys are always the ones that are down first. She watches as Dean, Castiel and Balthazar file into the dining hall. Balthazar, being new to the dinner table casually assumed the position of Dean's usual seat opposite Castiel.

Before Castiel can burst out in protest, Ruby drags him off to the side speaking in hushed tones, "Don't make a fuss about this seating arrangement will you? It's just for a while. Dean will be sitting beside you so it'll be alright. You just have to bear with it for now."

Castiel growled, pulling Ruby's hand away from where it was on his arm, "He needs to learn that this is our place he's here on our hospitality so he can't just go around taking our seats," he says loud enough as he shoves past Ruby now and sits opposite the Warlock with an obvious dark mood.

Balthazar fought to keep down the bitter taste of resentment and irritation at the comment but he couldn't help it, he'd thought Castiel to be so much nicer, "Well, someone's in a bad mood. Wonder who dared to piss off the oh-so-great Shadowhunter today, bet that was one unlucky person," he says feigning ignorance.

Castiel glowered with anger, forced to keep quiet for the sake of keeping the peace at the table. He knew how Ruby liked to have peaceful dinners, or at least as peaceful as things could get.

"Thank you," Balthazar said to Ruby when she passed him the jug of juice that she had prepared, "at least some Shadowhunters know how to treat the higher ups with manners." He didn't know why but he wanted to see how far he could push Castiel, it was truly amusing. "Now you were talking about the sudden rise in…Ouch! What was that for?"

Castiel smirked at Balthazar's exclamation, "Oh sorry, that was your foot Balthazar? I couldn't see it because Warlocks are always making parts of themself go invisible," he said stifling his laughter together with Dean beside him who was taking a long drink and trying hard not to laugh either.

"Alright this is seriously getting fucked up," Balthazar said irritated now. Clearly Castiel was ganging up against him with Dean. "Is this how your great Nephilim hospitality is like? I bet even those wayward vampires can do better than you," he said directing the comment to Castiel before he turned to Ruby, "I must thank you for the meal but it seems that I am not welcomed here by some," he said glaring pointedly at the two Shadowhunters who were still trying not to laugh before grabbing his plate and standing, "I will be in my room if you need me."

The moment the Warlock had left the room the two Shadowhunters burst out into laughter. Dean swiping tears from his eyes now before he calmed down, "Well you really hate the guts of that guy huh," he says pushing the food around on the plate, he wasn't about to eat it. Ruby's food wasn't the best and well the few times he had eaten it, it had only ended up in him having a really bad case of diarrhoea.

Castiel was exasperated, "You don't get it Dean! He was checking up on me he just won't admit it. I saw those papers he had about me…with my name and all my information on it. It was creepy as hell. And I don't know…" he paused shaking his head, pushing the food away now. "I'm not hungry."

"Cas what he spoke was the truth though, the Clave permitted his entry for half the reasons of providing shelter, and the other was to investigate the string of unsolved demon sightings. Bobby's given him the right to stay here, I guess maybe he just wants to know more about the inhabitants you know?" Dean said taking another drink of the juice, "How about we do some sparring later to work that frustration out?" he asked grinning at the other, he knew a good sparring session would help to take away Castiel's frustration. It was always the best remedy.

"If he does, I wouldn't mind if he talked to us, I mean come on Dean, if you found him with papers containing your information wouldn't you be freaking out?" he asked seeing Dean shrug. He shook his head pushing back his chair now, still confused. If Balthazar had been wanting to know more about the inhabitants of those at the Institute, then wouldn't he had had other papers on Dean and Ruby as well? Why had there been only papers on him? He decided to take Dean up on his offer, "Sparring it is, lets go," he says as he grabbed his partner by the arm, pulling him along now in the direction of the combat halls.

Once they were there, Castiel changed into the training gear as he grabbed twin wooden rods, "How about pair training?" he says tossing one of the rods to Dean now who catches it perfectly, "So what're the rules?"

"Hmm, first to three points and no stamina runes. Aim to disable for round one, then round two we aim for the killing shot and–"

Before he could finish the Warlock was once again there in the combat rooms. Castiel acted on instinct, aiming to strike Balthazar. But the Warlock avoided the blow as he teleported to a safer distance wearing a triumphant smirk on his lips. "Watch it Castiel. I'm not part of your sparring terms," he said. He was intrigued by the fact that the Shadowhunters were not going to use their stamina runes. Well…he just wanted to get to know Castiel so he proposed this, "How about the two of you have a go at each other, without stamina runes. Winner takes me on after that. And I won't use magic."

Castiel smirked, how foolish the Warlock was. He batted Balthazar with the wooden rod once more in acceptance of his challenge.

"Eager to fight aren't we?" Balthazar teased, loving the way Castiel's blue eyes flashed with the spoil for a fight. He couldn't wait to see who came out on top.

Castiel glared at Balthazar who calmly took his seat on the sidelines with another cocky smirk, "Oh he's all mine Dean. Sorry but I'm going all out on you," he strikes his partner quick and fast, taking Dean by surprise as he quickly disarms him, the wooden rod clattering to the side now leaving Dean with his hands as his only form combat.

He focused on the killing strike now since that was the second point. He blocked Dean's blow now, smiling as their eyes met, "Mmm you still fight good with your hands," he says hearing Dean grunt in acknowledgement now. Castiel of course doesn't want to hurt him but his yearning to put Balthazar down is even stronger.

Dean of course knows that Balthazar is interested in Cas, he knows that the Warlock has been interested in him from the moment since they met. Which is one of the reasons why he doesn't put up a resistance when Castiel kicks him away. He pretends that he is tired as he struggles to get back up on his feet slowly.

"There," Castiel exclaims, triumphant as he holds the rod to Dean's chest, the Shadowhunter lying flat on the mat. He is panting from the quick workout and he swipes away sweat from forehead, "two rounds since we were interrupted when he came in," he says nodding to Balthazar as he releases Dean from the wooden rod, reaching a hand to Dean to pull his partner up.

"Are you gonna be staying here Dean?" Cas asks him as he stands, brushing the dirt off of him. Dean shakes his head running a hand through his hair, "Seems pretty intense here. I think I am going to leave you two boys to work it out!" he says all grins as he turns to leave, waving absently as he slips out of the training room.

Castiel is already prepared for the next round. He is prepared to beat an answer out of Balthazar. He hands the Warlock the wooden rod and unintentionally his hand slips, brushing against the other's hand.

Balthazar shivers at the tingle racing up his arm from just that small brush of Castiel's hand, attempting to shrug off the obvious attraction to him as he prepares for battle. "Seems like you Nephilim truly live up to your name then," he commented, taking in Castiel's ragged appearance, "Fast, vicious, and pretty much ruthless. Deadly as well," he said grinning. He has his shirt off with the snap of his fingers, magic, "It can get pretty hot in here Castiel," he said nodding to the Shadowhunter's singlet that was sticking to his lean body, damp with sweat.

He noticed the way Castiel's eyes gave him a sweeping glance and had to stop himself from smirking, "Wonder if those that created the stamina runes had anything else in mind, for any purpose apart from combat..." he says more to himself but loud enough to get Castiel's attention. He likes how the Shadowhunter's cheeks colour in embarrassment at the suggestive remark and he knows now just what Castiel was thinking off as well.

"Don't make such crude comments, the stamina runes were created for fighting purposes only," Castiel replies as he averts his eyes now, feeling awkwardly hot now that Dean is gone and Balthazar and him are alone. The Warlock just standing there spinning the rod in his hands, topless. _'Of course the stamina runes could be used for other things…'_

"So, up for dinner? I missed quite a bit of it just now and Ruby's cooking is really…extraordinary. Maybe we could catch a movie, hang out after that...?" he says not knowing how or why he had gone and said that to Castiel.

_'The nerve of him!' _Castiel wanted to sock him in the face, "For your information I'm still angry with you for digging information on me and not telling me why. So the answer is no. I'm not going to go anywhere with you…" he paused then reconsidered it for some reason, "though we could use that as one of the criteria for the fight," he said, seeing Balthazar's eyes light up in interest. "If I win you leave the compound. If you win I'll…go out with you…and you promise you're not going to use any magic for this?"

Balthazar nods, "I promise. It'll be a fair fight," he says.

"Good. Three rounds then. First to disarm, second is hand combat and third we continue with the hand combat and deal the killer blow. Alright?" Castiel asks looking to the Warlock once more his eyes lingering a little to long on Balthazar's toned chest. It was very distracting. He finally dragged his eyes away from that distracting swirl of hair around Balthazar's navel that led down into the band of his pants, getting into his fighting stance.

"Challenge accepted," he chuckled rolling his shoulders back, enjoying the not-so-subtle attention from the Shadowhunter. "I aim to win that date," he informed smirking and taking advantage of the moment of distraction. Castiel was clearly attracted to him, though he so strongly denied it. Just like that Balthazar has won the first round with a quick blow to both the wrists and disarmed the Shadowhunter.

Castiel growled, throwing the stick to the side roughly letting it clatter noisily to the ground and making a show of how displeased he was. "No more dirty tricks for this round," he said narrowing his eyes as he stared the Warlock down before attacking.

"Fuck!" Balthazar hissed as he reeled back from the Shadowhunter's punch, "okay you pack a mean punch I get it," he teased riling up the other as he ducked and narrowly missed the second blow, feinting then moving in from the side to deal a quick upper-cut. "Now that we are eve-shit!" he cussed as Castiel struck him again. This time Balthazar came away with a bleeding lip, he drew in breath through his teeth now, tongue flicking out to lick away the blood, "Okay, round two to you," he said panting, equally tired, "Try not to disfigure my face though, I rather like it."

Castiel smirks, enjoying the session more than he had expected. He had to say that the picture of a beaten and bleeding Balthazar looked rather good. He stretched, loosening the kinks in his joints for the last round.

They met each other blow for blow, a smooth dance of lethal moves, each intercepting the other's strike just at the right moment. Castiel gasped in surprise when Balthazar drew him close as they grappled, their heated breaths mingling. He heard the Warlock chuckle, "You do really have pretty eyes, you know?" he says. Castiel hates it when he says such distracting things it makes him want to grab the Warlock and shut him up with a kiss. Instead he knees Balthazar and aims a blow for his jaw.

"This has got to be the most hard-earned date I have ever gotten," Balthazar remarks swiping the back of his hand over his lips now and coming away with blood. Damn Castiel was good at hand to hand combat and making him bleed. "I figure I might as well explain it to you now, before you try to ruin my face again," he says as he feints backwards, dealing another blow to Castiel's side.

"I did research on you, albeit it was an accident. Or not," he added hastily when Castiel came in for another blow to the face, "Can you blame me? Cute eye-candy in amidst of those dusty demon tomes, which information do you think I would read up on first? You, of course." _'I like you.' _ Balthazar tackles Castiel to the floor, trying to pin him down but the Shadowhunter is fast, writhing out from under him and trying to crawl away.

Castiel is panting wildly now and he can feel Balthazar's hands on his ankles dragging him backwards. Still he struggles, trying to crawl away. He yelps when he feels strong hands on his waist, a strong vice like grip on his hips as he is yanked back and pinned to the mat. Castiel is flipped onto his back, chest heaving as he glares up at Balthazar who is towering above him. "I win," he hears the Warlock rasp before he leans in to capture the lips.

Balthazar smirks into the kiss tasting the sweat, the slightly coppery taste of blood and sweet sense of satisfaction as he feel's Castiel's body beneath his, heart racing against his chest.

Castiel of course does the obviously right thing and tries to fight Balthazar off. He fails though and ends up moaning into the kiss instead when the sneaky bastard slides his leg in between his own, his knee gently pressing against Castiel's growing erection. "B-Balthazar…" he gasps then swallows, panting for air. He is still trying to fight the Warlock off and is miserably failing. Castiel finds himself kissing Balthazar back now, tasting the metallic tang of blood on his tongue as lets his tongue trace the outline of Balthazar's lips.

"Fuck…" he cusses, he rarely cusses. The feeling of kissing the Warlock is too damn intoxicating and Castiel wants more. He parts his legs, a needy gesture, to accommodate Balthazar who kneels between his legs. Then he wraps them around the Warlock's waist and locks his ankles behind his back. "Mmph…oh god," Castiel pulls him closer, his lips parting as he slides his tongue against Balthazar's. He tastes so good.

Balthazar groans at the way Castiel is so needy beneath him. So vocal too with the way he cusses then calls on god. The Shadowhunter's hands going to fist in his hair, massaging his scalp before slowly moving down to gently knead his neck and then rake down his bare back. Castiel's hips were unknowingly thrusting up into him, and the Warlock grows harder at the constant friction and pressure on his own erection.

Castiel pulls away roughly then, shocked at his actions and still panting. He lets out a shuddering breath before speaking, "Balthazar…what the fuck…" he whispers, chewing on his bottom lip as he lies there, looking up into the Warlock's lust darkened eyes, gathering his thoughts. His hands dropping from around Balthazar's waist, as he opens his mouth to ask the next question, "What are you trying to say?"

"That I like you," Balthazar says as if it is already not obvious enough, he slips his hand into Castiel's, twining their fingers together, "You are an obnoxious and rather rude, Shadowhunter, but you are also strong and hot as hell and I can't deny the attraction I have for you," he says as he leans in and indulges in another deep, passionate kiss. This time he takes it slowly, showing Castiel just how gentle he can be. He feels Castiel's hand running down his bare side, caressing his skin and he shudders, finding himself rolling his hips into Castiel's own.

"Shit…" he whispers, eyes still closed as he leans his forehead to Castiel's, "Damn these sexual urges," he growls. Pulling back now, rather reluctant, "We could always continue you know? Unless you would rather go on our date since I won," Balthazar teased him.

Castiel smacked him lightly on the shoulder, "Shut up," he says flustered, "I…don't mind it…I mean I'm game to try out new things…" he paused swallowing, a little laughter escaping his lips when he noticed Balthazar's erection, "Well you're certainly eager to have more than just two kisses. But I'm not going to jump in so quickly though," he says moving so that his lips are by Balthazar's ear, "So solve your hard cock yourself Balthazar."

He pulled back now, smirking as he saw the Warlock's stunned face, "I did only promise you dinner and a movie and as a Shadowhunter I must honour my promises. So," Castiel pushes Balthazar off of him, standing now, his cheeks still heated as he looks down at the topless Warlock, "I'll see you later at 7 in the main hall Balthazar. In the mean time you should really do something about this," he says and teasingly prods Balthazar's crotch with his toe, smirking again at his hardness.

Balthazar lets out a disappointed sound, shocked at just how bold Castiel can get. Yet his cheeks still colour in embarrassment as he walks out of the training room with a casual, "I'll see you later."

"Fuck…" Balthazar hisses as he stands, "now for that damned cold shower."

_-FIN-_


End file.
